Table 3 Adjusted odds ratios (OR) and 95% confidence intervals (CI) for tuberculin skin tests (TST) of ≥ 10 mm and positive interferon-γ release assays (IGRA)

Age

N (%)

OR

95%CI

N (%)

OR

95%CI

< 25 years

223 (74.1)

1

--

57 (18.9)

1

--

25-29 years

532 (64.8)

0.6

0.5-0.8

204 (24.8)

1.3

0.93-1.8

30-39 years

553 (69.9)

0.8

0.6-1.1

266 (33.6)

1.9

1.4-2.6

40-49 years

424 (79.4)

1.5

1.0-2.1

219 (41.0)

2.3

1.6-3.3

≥ 50 years

370 (84.7)

2.0

1.4-3.0

207 (47.4)

2.7

1.9-3.9

Gender

Female

1,487 (71.9)

1

--

658 (31.8)

1

--

Male

615 (75.4)

1.2

0.97-1.4

295 (36.2)

1.1

0.9-1.3

BCG vaccination

Only at birth

700 (76.3)

1

--

406 (44.3)

1

--

One additional

741 (72.5)

1.0

0.8-1.2

330 (32.3)

0.7

0.6-0.9

Two additional

460 (69.4)

1.0

0.7-1.2

165 (24.9)

0.6

0.5-0.7

3-10 additional

201 (71.3)

1.0

0.8-1.4

52 (18.4)

0.4

0.3-0.6

Profession

Administrator

302 (77.8)

1

156 (40.2)

1

--

Auxiliaries, cleaning staff

335 (68.8)

0.8

0.6-1.1

180 (37.0)

1.0

0.7-1.3

Technicians (radiology, lab, etc.)

137 (80.6)

1.6

1.0-2.5

54 (31.8)

1.0

0.7-1.5

Nurses

864 (71.8)

1.3

0.95-1.8

317 (26.3)

0.8

0.6-1.1

Physicians

464 (73.1)

1.2

0.9-1.7

246 (38.7)

1.4

1.04-1.9

Risk assessment

Low risk

176 (85.4)

1

--

85 (41.3)

1

--

Moderate risk

1,289 (74.9)

0.6

0.4-0.91

549 (31.9)

0.8

0.6-1.2

High risk

637 (66.6)

0.4

0.3-0.6

319 (33.4)

0.9

0.7-1.3

Years working in healthcare*

Start of work

289 (72.3)

1

--

112 (28.0)

1

--

< 1 years

84 (59.6)

0.6

0.4-0.92

26 (18.4)

0.7

0.4-1.1

1-5 years

502 (63.8)

0.7

0.5-0.91

211 (26.8)

1.1

0.8-1.4

> 5-10 years

324 (69.7)

0.9

0.7-1.2

154 (33.1)

1.4

1.06-2.0

10-20 years

454 (79.2)

1.5

1.1-2.1

212 (37.0)

1.6

1.2-2.2

≥ 20 years

449 (86.7)

2.5

1.8-3.6

238 (45.9)

1.9

1.4-2.5